Syntax

For character strings, if both the left and right operands
are of type CHAR, the resulting type is CHAR; otherwise, it is VARCHAR. The
normal blank padding/trimming rules for CHAR and VARCHAR apply to the result
of this operator.

The length of the resulting string is the sum of
the lengths of both operands.

For bit strings, if both the left and
the right operands are of type CHAR FOR BIT DATA, the resulting type is CHAR
FOR BIT DATA; otherwise, it is VARCHAR FOR BIT DATA.